Development of a quantitative energy filtering TEM method to study a reactive NiO/80Ni20Fe interface

Energy filtering TEM (EFTEM) has been performed on an annealed NiO/80Ni20Fe interface. Chemical maps have been calculated using the three-window technique on the O–K, Fe–L23 and Ni–L23 edges. In this paper we show that relative quantification can be made using reference areas on the images taken from part to part of the interface in well-known composition areas. Partial cross-section ratios σNi(20 eV)/σO(20 eV) and σNi(20 eV)/σFe(20 eV) have been then measured and used to extract the chemical composition of the reactive NiO/80Ni20Fe interface. Fe, Ni and O composition profiles across the interface have been obtained showing the diffusion process which has occurred during annealing. The reliability of the EFTEM measurements has been checked by EEL spectroscopy on the same sample as well as on a reference geological oxide sample (Trevorit: NiFe2O4). The partial cross-section ratios obtained with the two methods (EFTEM and EELS) are in good agreement.